Apparatus for removing impurities from furnace-gases.



PATENTED MAR. 12, 1907.

R. BAGGALEY. APPARATUS FOR REMVING IMPURITIES PROM IURNAGE GASES.

APPLICATION FILED NOV.27. 1903.

A R N n m S. NN W Y @Nl E I @JH o Q G /Q @A e .I www5 LWN www; am@ 6.@

WITNESSES RALPH BAGGALEY, OF PITTSBURG, PENNSYLVANIA.

APPARATUS FOK-'i RElVlOt/hl@ lillPUFllTltS FHW FUiUlNACEMGSESD Specication of' Letters Patent.

atented March 12, 1907.

l'lriginai application lled September 24C, 1903, Serial No. 174,432. Divided and this application filed November Z7, 1903.

Serial No. 182,755?. l

T0 all whom, it may concern.-

Be it known that l, RALPH BAGGALEY, of Pittsburg, Allegheny county, Pennsylvania, have invented a new and useful Apparatus for Removing impurities from Furnace Gases, of which the following is a iull, clear, and exact descrij'ition7 reference being had to the accompanying drawings, forming part of this speciiication, in'wliich Figure l is a vertical cross-sect1' on oi apparatus embodying my invention, the sectionplane extending through one oi the charcoalcontaining chambers. Fig. 2 is a side elevation partly in vertical longitudinal section. Fig. 3 is a perspective view, on a larger scale, showing the cutter-bar mecl'ianism 'ler re 'moving from the walls incrustations deposited from the iunacegases.

My invention is designed to prevent they devastating effects lto vegetation and tothe streams arising from the smelting olveopper ores containing sulfur, arsenic, &c. it is well known that the country surrounding smelting plants, sometimes for many miles distant, is devastated through the destruction of vegetation by the fumes inseparable from the fusion oi sulfid ores. f

In a furnace smelting three hundrediand sixty tons of ore that contains, say, twenty per cent. of sulfur from sixty of seventy-'live tons oi' sulfur are volatillzed daily and of course deposited 1n the surrounding country.

On damp or rainy days the sulfur will fallwithin a short dista-nce of the smelter-staek,

On clear days it will often be carried ior a distance of iiiteen or twenty miles. The re sult is the same whereverit falls. Vegetation is destroyed, and the'sulfur is carried by the surface drainage into the streams and ponds and the water is polluted and rendered uniit for use. A still more injurious eil'ect is produced .when the ores contain arsenic, which is alsoA volatili zed and when carried into the streams renders the water poisonous. So serious has this become that itis impossible to operate smeltirnT plants and to conduct agriculture successfully in the same district. My invention is intended not onlv `to prevent in an economical manner these l objectionable features ei the smelting industry as at present practiced, but at the samev time when desired to collect as byproducts l l l My invention is founded on the fact that charcoal will absorb irem forty to i'iity times its volume of suliur and sulfur-dioxid gases. .ln the smelling ci suliid ores approximately one-halt the sulfur contents of the ore pass oil in the forni ot l'ree sulfur. The remaining gases contain irem fourteento iifteen per cent. oic sulfur dioxid and are practically iden tical with the gases produced by roasting pyrites in. the hilns employed in sulfuric-acid manufacture. l have found that by interposing charcoal screens or 'lilters within`enlarged chambers located between the smelting-furnace and the stack or located between. the smelting'lurnacc and a suitable fan or other mechanical device 'for producing an in duced draft 'these obnoxious sulfur-nimes will he absorbed eilectually up to the point wl'iere the charcoal has been increased approximately twenty per cent. oi its weight. Above this point the sulfur-,fumes are not entirely arrested. Therefore if it desired in practicing my invention to remove all of the sulfur from the fumes the charcoal must be changed whenever its weight has been increased by such deposit and absorption apprcedmately twenty per cent. In ordinary practice it will not be necessary to eliminate all ciY the sulfur. li' twenty per cent. of the sulfur-fumes, l'or example, is allowed to escape, the fumes will be so dilute as to readily become dissipated in the atmosphere without serious injury to the surrounding country.

ln a furnace that smelts three hundred. and liity tons of ore in twenty-four*hours containing, say, twenty per cent. of sulfur the daily output oi' sulfur released, either in the free state or as sulfur-dioxid gas, will approximate sixty tons. Theoretically this would require for purification ol the gases a ton and a half of charcoal daily. ln my apparatus I provide successive filters, preferably three in number, each containing from t wo to two and a half tons of' charcoal. These should be located far enouglifrom the smelting-ur nace te prevent ignitiony from the hot gases. I have found that charcoal is subject to what is called in the trade spontaneous combustion," which l believe to he caused by the vgeccurrence of red-hot centers protected from IOO l I the atniosphere b`\ a casiiiil oll cold iion-coiiductingr charcoal and which when exposed io airhurst into llaiiic. lt is therefore oll iinportance that provision he made l'or dieiicliingr the chareoai screens l'i'oiii above with water. lt isalso important' oii account olA the large and rapid deposit ot impurities troni the gases that the charcoal ilteriiicr iiiateiial he renewed l'refpieinly, anty or this purpose l. provide the chambers which contain such material with mechanism situated in the column of liltei'inry material l'or etlectingfposiw tivelY the removal olI such material, either e continuously or interniittentlvA as desired,

and as the material is thus removed l'roin the y bottoni of the chamber fresh material is int When the 3 charcoal has heen removed, l preferably introduced t-hereinto at the top.

traduce it into a Steam retort or tank, where the contained sulfur is melted out hv means of steam under a pressure otl approximatel)v titty pounds to the square inch. This lvields a temperature of approxiniatel)- 300 Falircnheit, and as sulfur melts at 239 FahrenheitI itl is apparent that the sull'ur is thus reinoved .troni the chareoai and the charcoal rendered capahle ot' heing used airain torrthe saine purpose rl`he third screen provided in my apparatus also contains charcoal which is eonstantl)v drenched or saturated either with. a dilute solution oll sullid ot' calci '-iii or with ii simple alkaline solution ol any kind that can he cheaply and readil)Y ohtained. Such solution can be used man v tinies'and will etl'ectualhv throw down and arrest thc arsenic contained in the gases. B v resuliliming the sull'ur in the steani-retort ahove referred to it may he treed t'i'oiii all bases, impurities. iead. zinc., '.Qc.. exeeptingir j Should the sullur he tound to coui tain arsenic in any appreciahle percentage, it.

arsenic.

will not be. lit l'or use: but the arsenic can be eliminated hv suitable treatment.

ln order to secure the most effective results in thi` operation ot from the walls. portion of the deposited impurities will precipitate as a hard iiiassin the llues on the interior ol the thiewi'allsduid especially around the interior edges of each llue, and as the tonnage precipitated is very great such accumulations ot incrustations,

lsrgfare, necessarily quite rapid, and in time projections of precipitated material on the interior ofthe. line-walls will intertere with and obstruct the draft and in time may elogir and obstruct the travel ot the screens.

It is important that these olisteuetions he quickly and cheaply removed lioni the iiii torior walls so often as ma)Y he desired and in such a manner that the apparatus will not.

apparatus such as i described above, it is necessari' to provide means for reinoviner thi` incrusted inipiirties ,t

l'ie"tliro\\'n out of service or its successful' workinii' he delayed or interfered with. It is also ot' importance Vthat this work should he accomplished without manual labor. i efl'ect the removal ot' these hard iiicrustations hv the use ot cutter-hars actuated bv suitahle mechanism which maintains them in inotion alongr the surface ol" the llue-walls. so that they will t'orcihlv dislodge the incrusta tions, and thus keep the llues t'reelvoi'ien for the passage olI the gases.

ln the drawing. in which l show the pret'- erable construction otE in v apparatus. Itis a cliaiiiber connected at one end with the downcomer pipe ol a smelting-furnace and at the other end communicating with a stack or other means for drawingr the siiiclt'er-gascs rapidtv through it. The chaiiiher is provided at intervals with f the screens above mentioned. VEach screen i is toriued h v vertical douhle walls 4 si'. having pert'orations .-3 5, which are inclined upwardlv l 1n order to prevent loss ol: the .charcoal contents aiid otl'er free passage to the sine-ltei- I gases. Each screen-elianiher has at its upi per end a feeding-space n. preferably lorined with upwarttlv-converging: walls and coinnuinicatiii;r with a feed-hopper 7. and at its lower end it terminates in a space S, provided with a screw convever t) or like discharging. mechanism adapted material at an opening 1t). This convever situated in the hase oiC the vertical column olhlteriiifr material, so that it is e'll'ective to ause a read)Y removal of the material not-- withstanding the versir large amount of iinpurities which are deposited upon the pai'- l tieies ot material and which, consisting i largeiv oi" sultur and sulfurcompound, would material and its lodgnient within the screen chainher. ,Owing to the large volume of l binding-agents which are deposited upon the j littering.: material l'roin the coppersinelter i (fases. 1t is essential that the screw conveyer he placed in the vertical column, for otherabove stated. In this respect in vapparatns At, the eiidsol the screen s )aces or chambers are openings It, titted' with suitable doors l l| ditlers troni all others heretofore proposed. f

pokingstool when it is desired to facilitate the discharge ot the contents. At the upper end i ot: each sereeiicliaiiiheiare pipes 13, bv

which water or alkaline solution may he.

introduced in quantities, as vdesiredl The lresh charges of charcoal are tied into the hopper h v spouts or chutes 12, which lead lrom suitable sources ot supply, so that the E feedingr and discharge of the charcoal inavP hg. i etl'ected without manual labor. In use of otherwise tend to canse the scatlolding of tho and adapted to pei-init the admission of a.

to discharge the screen IOO wise the material would clog or scaffold, as

the apparatus the screei'icliambers betweenthe perforated walls .are filled with charcoal introduced through the hoppers, and the charcoal of the third screen is kept drenched from the pipe 1.3 by a simple alkaline solution or a solution of sul'lid of calcium for the sole purpose of precipitating any arsenic` In order to present fresh charcoal. surfaces to the gases from time to time,'a part ol tlm charcoal is withdrawn at "the bottom ole the screen-chambers, its place being taken kby charcoal fed through the hoppers, the rapidity of the withdrawal of the charcoal being governed by the percentage of impurities contained in the ores under treatment. ly causing the charcoal to pass rapidly' through the column the danger oiC scallolding can prevented, and, it desired, the cl'iarcoal caribe passed repeatedlyT through the vcolumn by reintroducing it at the top of the column it is removed trom the base thereof.

The cutters by which the h'i' i incruste tions deposited on the walls .i dislodged are preferably constructed as follows: l5 l5 are bars which extend horizontally across the screen-chamber and are connected by vertical rods i6, set in grooves in the masonry walls and adapted to be reciprocated by links 17 from cranks 1S on shafts le. rlhe bars lniay be made o'r' lard wood Jfaced with brass or other material not corrodible by the furnace-gases, or they may be made entirely ot brass. 'lhe hars on opposite sides of the screen cham hers are moved by the cranks in opposite directions, and thus constantly lfree the interior et the chamber from incrustations, allowing the hiltering material to drop readily witlnuit obstruction. The upright bars or rods which carry the cutter-hars are sunk in vi cal .grooves in the walls of the llues, in which manner they are protected from the action ot 'the gases and are also partially protected ,trom ,the action olE the water and the alkaline solutions on the filtering material. lllach cutter-har when at rest is-shielded and protected troni the action of theI gases by reason of its posi-- tion between the {lue-inou Each upright bar is provided with guides 'both above and below that hold it rigidly in the exact positionneccssaryto enable tlic,c1itte1'bars to do the most effective worl: in their mission of removing such incrustations and precipitated materials. The cutter-bars themselves may Work continuously and slowly or intermittently and rapidl as may he found in practice to best suit t ie worl: and to produce the most economical results in each plant where my invention may be utilized, and at the corners of the screenszhambers the cutter-bars 'may be given an angular form, ,as

shown in'Fig. 3, in order to operate upon the end walls of the chambers aswell as upon the side walls.

The present application is a division of an application filed by me on September 24, 1903', Serial No. Ude/i552.

l claim-- l. Means for removing impurities from copper-smelter gases, comprising a vertical column ol screening material interposed across the path of the gases, means for supplying fresh material to the top ot the co1- umn, and a conveyor situated directly in the base of the column, the said column beingunobstructed 'throughout its height and resting upon the conveyer, whereby the screenfree to move downwardly therein, together I with means tor supplying material to the upper end ot the column and removing it from the lower end substantially as described.

3. Means for 'removing impurities from coppersmelter comprising Va chamber into which the gases are led from the smelter, a screen interposed in said chamber, said screen consisting' of straight vertical column of granular material inclosed between perforated lateral walls, and a conveying device at the hase oi' the column, the cross-sectional arca. of the column where it discharged to 'the conveyor being unrestricted, whereby the column is 'lree to move downward as tast as .its lower portion is removed by the conveyer; substantially as described.

L ill/leans 1for removing in'ipurities from cf pper-srnelter gases, comprising a chamber to whici'i the gases are led from the smelter, and are tical screen in said chamber transverse to the passage of the gas,said screen compris-ing parallel vertical walls having unobstructed inner surfaces and formed with upwardly and outwardly directed. perforations or o'ienings, a column of granular ma* tcrial between said' walls and extending unobstri'lctedly below the same into an enlai-ged conveyenchamber, and a cnveyer uponwhicli the base of the column rests;v

i substantially as described.

llleans removing impurities frein copper-amelter1 gases, com )rising a chamber to which the gases are le trom the smelter,

and a vertical screen in Said chamber transverse to the passage of the gas, said screen comprising parallel vertical Walls .having unend; subswutully as described..

obstructed inner surfaces and 'formed with .ln 'lzestmuny whereof I have leleuno set l together with means for spraying the column i l I 1 l 5 upwardly and outwardly duect-ed perfumf my hzuul,

and for supplying fresh materlal to its upper tlons 01" openings, ay Column of granular um telial between SaidA Walls, and extending un- RALPH BAGGALEY' v obstructeclly below the same into au en- Vftuesses: lax'ged' eonveyer-chamber, and a, eonveyer i WILLMM M. RIRKPATRICK, m upon Wluch the baseof the column rests, .y W. D. KYLE. 

